Weighted crunches. Just cos the weight I do them on is considerably larger than any other weight I do. Makes me feel like a real man picking up those big beast weights.
Jenn you are such a dirty girl...but I like that exercise too. As for using weights, I've been really feeling the reverse curls lately, because it pumps your entire arm and it feels great. Other than that, maybe bench, because the pump I get in my chest.